Question

If the selling price of 20 articles is equal to the cost price of 25 articles, what is the gain percentage?

• A. \(20%\)
• B. \(25%\)
• C. \(30%\)
• D. \(35%\)

Hint:

If the selling price of \(x\) articles equals the cost price of \(y\) articles, then \[ \text{Gain %} = \frac{y-x}{x}\times100 \]

Answer 1

The Correct Option is B

Concept: Profit or gain percentage is calculated using the formula: \[ \text{Gain %}=\frac{\text{Profit}}{\text{Cost Price}}\times100 \] If the selling price of some articles equals the cost price of a larger number of articles, then the seller is making a profit.
Step 1:Forming the relation from the given condition.
Let the cost price of one article be \(C\) and the selling price of one article be \(S\). Given: \[ 20S = 25C \] \[ S = \frac{25}{20}C = 1.25C \]
Step 2:Finding the profit per article.
\[ \text{Profit} = S - C = 1.25C - C = 0.25C \]
Step 3:Calculating the gain percentage.
\[ \text{Gain %} = \frac{0.25C}{C}\times100 = 25% \]